No audio on external calls

[ITSD]

We have an audio problem with a new Yealink W52P phone connected to a 3CX PBX.

Calls can be placed from the phone to internal extensions or external numbers, audio is good in both directions and call quality is excellent.
Calls can be received by the phone from internal extensions, audio is good in both directions.

Problem:
When an external call comes in there is no audio both ways:
1. The phone rings
2. The user is able to answer the call and the call is connected
3. The user is unable to hear the caller and the caller doesn’t here the user (No audio is received in both directions)
4. If the user puts the call on hold and then resumes the call two way audio is restored.
5. The call needs to be answered, quickly put on hold and then resumed for two way audio to function properly.
6. This issue affects 100% of inbound calls to this phone from external numbers.

PBX: 3CX v11
Yealink W52P Firmware: 25.30.0.40
Yealink W52P Hardware Version 25.1.0.0.0.0.0

Both phone and PBX are on the same subnet connected to the same network switch.